The most traditional way of positioning a flat dental X-ray imaging sensor in the mouth of the patient and against the patient's teeth is simply to put the separate sensor in the intended place, and ask the patient to keep it against his/hers teeth by his/hers finger. This procedure has been used both for the photographic film sensors and for the electronic imaging sensors. This procedure is simple and cheap, but attaining the correct place and position—e.g. tilt angle—is quite unreliable, as is keeping the sensor stationary during X-ray exposure. It is suggested several types of special holders, in which the electronic X-ray imaging sensor is attached, to overcome these problems.
The patent publication U.S. Pat. No. 6,203,195 B1 discloses a holder, which accommodates dental sensors of various dimensions for receiving X-rays and thereby transmitting signals showing the condition of a patient's teeth to a computer or other recorder. This holder is provided with a clasp engaging one edge of a sensor while adjustably movable to cause a fixed portion of the holder to engage the opposite edge of the sensor. Interfitting ratchet teeth on clasp and holder retain the parts in the required position, and a protruding handle portion and an arm portion are also provided for positioning the sensor within the teeth of the patient in the desired position. The publication also suggests the use of a different holder acting as a bite block for holding the patient's jaws apart in certain occasions. The sides of the bite blocks are non-parallel, thereby reducing the shadows of such sides on the X-ray usage. This kind of sensor holder is quite complicated rendering it expensive, and difficult to sterilize. Its use in practice is also very cumbersome. The sensor can be placed only in such position, in which the signal cables from the sensor are in the direction perpendicular to the elongated shank.
The patent publication U.S. Pat. No. 6,520,676 B1 discloses a holder used in dental radiography being substantially an ultra-thin bite wing with a reinforced juncture between the bite wing and the integral sleeve such that a perpendicular orientation is maintained while the sensor is in the patient's mouth. The dimensions of that invention allow the patient's teeth to be in close proximity while an image are formed using the sensor, and the disposable sensor provides a mechanism for indicating a previous use to ensure single use. The holder is formed using an injection molding process of polyethylene of 40 to 80 melt flow, with a preferred melt flow of 60. The thin bite wing is enabled because of a reinforced T-joint at the base of the sleeve along the spine connecting the bite wing, which maintains the sleeve and the holder in a perpendicular orientation with respect to the plane formed by the upper and lower surfaces of the mating teeth. This holder does not include any handle at all, but the sensor is kept in place by the bite wing positioned between the teeth. The bite wing here is not intended to hold the patient's jaws apart, accordingly being a contrary solution to the bite block according to U.S. Pat. No. 6,203,195 B1 mentioned above. The sensor can be placed only in such position, in which the signal cables from the sensor are in the direction parallel to the bite wing.
The patent publication U.S. Pat. No. 6,461,038 B2 discloses a holder for a dental X-ray image sensor that comprises a handle having a first end. The first end of the handle is connected to a first elastic loop. The first elastic loop holds the dental X-ray image sensor. As a result of the combination of a handle and an elastic loop, the X-ray image sensor may be placed in the mouth and its position adjusted depending upon the individual patient's palate and the area lateral to the patient's tongue. The handle can further comprise a second end that is connected to a second elastic loop. The second elastic loop can also hold a dental X-ray image sensor. In such an embodiment, the second elastic loop is arranged transversely in comparison to the first elastic loop. The handle is preferably elongated and flat with an upper side and a lower side. When the first elastic loop is formed from an elastic strip having a first end and a second end, the first end of the elastic strip is connected to the upper side of the handle while the second end of the elastic strip is being connected to the lower side of the handle thereby forming a loop that extends outward from an edge of the handle defined by the upper and lower sides of the handle. Alternatively, the first and second ends of the elastic loop may be disposed in and secured in the horizontal slot of the handle to thereby fasten the loop to the handle. The opening defined by the elastic loop can thus be parallel to the upper and lower sides of the handle, or normal to the upper and lower sides of the handle. In a further embodiment, the publication discloses a saddle, which includes a back wall having two opposing ends.
Each end of the back wall is connected to a bracket having a U-shaped configuration. The brackets are arranged in an opposing relationship to one another. The elastic loop extends around the back wall and between the U-shaped brackets to secure the saddle to the handle. The U-shaped brackets then accommodate a dental X-ray image sensor between the brackets with the loop extending between the sensor and the back wall. Contrary to the solutions according to U.S. Pat. No. 6,203,195 B1 and U.S. Pat. No. 6,520,676 B1 the sensor can be here placed in two positions perpendicular to each other, but in the opposite ends of the handle. As a drawback, there shall be different holders for sensors of different dimensions, because each size of the elastic loop operates reliably and without damaging the sensor only for sensors having specified dimensions.